Squeak

Squeak, developed in 1996 by Dan Ingalls, Ted Kaehler, John Maloney, Scott Wallace, and Alan Kay, is an implementation of Smalltalk... in Smalltalk. Squeak implements a lot of the concepts that Kay focused on in his DynaBook (laptop prototype), KiddiKomp, and Smalltalk projects. Squeak emphasizes the open, fun nature of authoring media, in line with Kay's original vision of a language for expressing concepts naturally.

-> Squeakland!